The use of self-drilling rock bolts provides a rational procedure since the bore hole, into which the rock bolt is intended to bee inserted, is formed with the rock bolt itself as a drilling tool. After the drilling step a bolt grouting medium such as cement is injected into the bore hole for grouting the rock bolt for rock reinforcement purposes etc.
During the boring step the drilling area is flushed with pressurized air or with a flushing fluid which is alternatively flushed during the drilling step as a thin flowing cement which also serves for grouting purposes.
Such flushing can be continuous and results in a better penetration of the cement into the rock surrounding the bore hole and consequently better anchoring of the bolt.
A previously known device for rock bolting includes a swivel device which is screwed onto the neck adapter of the drilling machine. The other end of the swivel device provides a thread for receiving a threaded end of a self drilling rock bolt.
This previously known device is used for manually controlled rock bolting and requires monitoring by an operator when loosening the drilled-in rock bolt from the swivel device.